--- id: CVE-2025-11234 title: A flaw was found in QEMU summary: >- A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel.… severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H' cwe: - CWE-416 vendor: Red Hat product: qemu affected: - qemu >= 2.6.0 < 10.1.2 - qemu-kvm (all versions) - 'virt-devel:rhel (all versions)' - 'virt:rhel (all versions)' - 'virt:rhel (all versions)' - 'virt:rhel (all versions)' - 'virt:rhel (all versions)' - 'virt:rhel (all versions)' - qemu-kvm (all versions) - qemu-kvm (all versions) - qemu-kvm (all versions) - qemu-kvm (all versions) - qemu-kvm (all versions) - rhcos (all versions) - rhcos (all versions) - rhcos (all versions) - rhcos (all versions) - qemu-kvm - qemu-kvm - qemu-kvm-ma (all versions) - openshift/ose-rhel-coreos-9 (all versions) patched: - openshift_container_platform 4.12 - openshift_container_platform 4.16 - openshift_container_platform 4.17 - openshift_container_platform 4.18 - enterprise_linux_appstream_v_10 - enterprise_linux_appstream_v_8 - enterprise_linux_appstream_e4s_v_8_8 - enterprise_linux_appstream_tus_v_8_8 - enterprise_linux_appstream_e4s_v_9_0 - enterprise_linux_appstream_e4s_v_9_2 - enterprise_linux_appstream_eus_v_9_4 - enterprise_linux_appstream_v_9 - enterprise_linux_crb_v_8 published: '2025-10-03' updated: '2026-09-21' sourceUpdated: '2026-09-21T06:16:59.757' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-11234' references: - url: 'https://access.redhat.com/errata/RHSA-2025:23228' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:0326' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:0332' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:0702' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:1831' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:18772' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:22147' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:3077' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:3165' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:5578' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:59831' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:68513' label: secalert@redhat.com - url: 'https://access.redhat.com/errata/RHSA-2026:69131' label: secalert@redhat.com - url: 'https://access.redhat.com/security/cve/CVE-2025-11234' label: secalert@redhat.com - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2401209' label: secalert@redhat.com - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-11234.json - url: 'https://www.cve.org/CVERecord?id=CVE-2025-11234' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-11234' tags: - nvd - cve.org - csaf - vex - red-hat ssvc: exploitation: none automatable: 'no' technicalImpact: partial timestamp: '2025-10-03T15:56:54.379790Z' epss: 0.00864 epssPercentile: 0.57122 ingestedAt: '2026-08-21T13:17:18.038Z' --- ## Overview A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel. This can be abused by a malicious client with network access to the VNC WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client authentication. ## Remediation Refer to the linked advisories for vendor-supplied fixes and affected version ranges. ## Vendor advisories - **RHSA-2026:59831** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.12 · released 2026-09-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:59831) - **RHSA-2026:0326** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.16 · released 2026-01-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:0326) - **RHSA-2026:0702** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.17 · released 2026-01-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:0702) - **RHSA-2026:0332** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.18 · released 2026-01-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:0332) - **RHSA-2026:1831** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-02-05 · [advisory](https://access.redhat.com/errata/RHSA-2026:1831) - **RHSA-2026:5578** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · released 2026-03-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:5578) - **RHSA-2026:68513** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68513) - **RHSA-2026:22147** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.0) · released 2026-06-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:22147) - **RHSA-2026:3077** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-02-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:3077) - **RHSA-2025:23228** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.4) · released 2025-12-17 · [advisory](https://access.redhat.com/errata/RHSA-2025:23228) - **RHSA-2026:3165** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.4) · released 2026-02-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:3165) - **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 7, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 7, Red Hat OpenShift Container Platform 4 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-11234.json) - **RHSA-2026:69131** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69131)